Approval sheet
WR18X(W), WR20X(W), WR25X(W)
1%, 5%
Thick Film Power Chip Resistors
Size 1218,2010,2512
*Contents in this sheet are subject to change without prior notice.
Page 1 of 7 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet
FEATURE
1. High power rating and compact size
2. High reliability and stability
3. Reduced size of final equipment
4. RoHS compliant and Lead free products
APPLICATION
Power supply
PDA
Digital meter
Computer
Automotives
Battery charger
DC-DC power converter
DESCRIPTION
The resistors are constructed in a high grade ceramic body (aluminum oxide). Internal metal electrodes are
added at each end and connected by a resistive paste that is applied to the top surface of the substrate. The
composition of the paste is adjusted to give the approximate resistance required and the value is trimmed to
nominated value within tolerance which controlled by laser trimming of this resistive layer.
The resistive layer is covered with a protective coat. Finally, the two external end terminations are added. For
ease of soldering the outer layer of these end terminations is Tin (lead free) alloy.
Fig 1. Construction of 2512, 2010 Chip-R
Fig 2. Construction of a 1218 Chip-R
Page 2 of 7 WR18-20-25X(W)_V17 DEC - 2016